Sven (in Danish and Norwegian also Svend and in Norwegian also "Svein") is a Nordic first name which is used throughout Scandinavia, Estonia and Germany. The name itself is Old Norse for "young man" or "young warrior". The original spelling in Old Norse was sveinn (whence Eng swain, "servant boy"). Over the centuries, many northern European rulers have carried the name including Sweyn I of Denmark (Sven Gabelbart), who established Danish rule over Norway and successfully invaded England in the year 1002. An old legend relates the pagan king Blot-Sven ordered the execution of the Anglo-Saxon monk Saint Eskil.

In medieval Swedish "sven" (or "sven av vapen" (sven of arms)) is a term for squire. The female equivalent Svenja, though seemingly Scandinavian, is not common anywhere outside of German-speaking countries.

The Icelandic and Faroese version of Sven/Svend is Sveinn (pronounced Svay-dn in Icelandic).